diff --git a/SeungyeonJi/week7/2023-10-29-SumRootToLeafNumbers.js b/SeungyeonJi/week7/2023-10-29-SumRootToLeafNumbers.js
index 2f55c3b0..d36ac3ba 100644
--- a/SeungyeonJi/week7/2023-10-29-SumRootToLeafNumbers.js
+++ b/SeungyeonJi/week7/2023-10-29-SumRootToLeafNumbers.js
@@ -24,3 +24,5 @@ var sumNumbers = function (root) {
 
   return num;
 };
+
+
diff --git a/SeungyeonJi/week8/2023-11-03-.js b/SeungyeonJi/week8/2023-11-03-PartitionEqualSubsetSum.js
similarity index 100%
rename from SeungyeonJi/week8/2023-11-03-.js
rename to SeungyeonJi/week8/2023-11-03-PartitionEqualSubsetSum.js
diff --git a/SeungyeonJi/week8/2023-11-05-SubarraySumEqualsK.js b/SeungyeonJi/week8/2023-11-05-SubarraySumEqualsK.js
new file mode 100644
index 00000000..e69de29b
diff --git a/SeungyeonJi/week8/2023-11-05.MaximumSubarrayjs b/SeungyeonJi/week8/2023-11-05.MaximumSubarrayjs
new file mode 100644
index 00000000..3700a5b6
--- /dev/null
+++ b/SeungyeonJi/week8/2023-11-05.MaximumSubarrayjs
@@ -0,0 +1,11 @@
+var maxSubArray = function (nums) {
+  let maxSum = nums[0];
+  let currentSum = nums[0];
+
+  for (let i = 0; i < nums.length; i++) {
+    currentSum = Math.max(num[i], currentSum + num[i]);
+    maxSum = Math.max(maxSum, currentSum);
+  }
+
+  return maxSum;
+};
diff --git a/SeungyeonJi/week9/2023-11-10-LetterCombinationsOfAPhoneNumber.js b/SeungyeonJi/week9/2023-11-10-LetterCombinationsOfAPhoneNumber.js
new file mode 100644
index 00000000..7c28905f
--- /dev/null
+++ b/SeungyeonJi/week9/2023-11-10-LetterCombinationsOfAPhoneNumber.js
@@ -0,0 +1,38 @@
+let letterCombinations = function (digits) {
+  let result = [];
+
+  //alpha has map
+  const alpha = {
+    2: "abc",
+    3: "def",
+    4: "ghi",
+    5: "jkl",
+    6: "mno",
+    7: "pqrs",
+    8: "tuv",
+    9: "wxyz",
+  };
+
+  const dfs = function (i, digits, state) {
+    // base case (condition to sotp this recursive function)
+
+    // If we loop through digits.length time, we will return the result;
+    if (i === digits.length) {
+      result.push(slate.join(""));
+      return;
+    }
+
+    //dfs recursive case
+    let chars = alpha[digits[i]];
+
+    for (let char of chars) {
+      state.push(char);
+      dfs(i + 1, digits, state);
+      state.pop();
+    }
+  };
+
+  dfs(0, digits, []);
+
+  return result;
+};
diff --git a/SeungyeonJi/week9/2023-11-12-SplitAStringIntoTheMaxNumberOfUniqueSubstrings.js b/SeungyeonJi/week9/2023-11-12-SplitAStringIntoTheMaxNumberOfUniqueSubstrings.js
new file mode 100644
index 00000000..ec05edaf
--- /dev/null
+++ b/SeungyeonJi/week9/2023-11-12-SplitAStringIntoTheMaxNumberOfUniqueSubstrings.js
@@ -0,0 +1,24 @@
+var maxUniqueSplit = function (s) {
+  let wordSet = new Set(),
+    res = 1;
+
+  function checkUniqueSubstring(i) {
+    if (i === s.length) {
+      res = Math.max(wordSet.size, res);
+      return;
+    }
+
+    for (let j = i + 1; j <= s.length; j++) {
+      let str = s.substring(i, j);
+      if (!wordSet.has(str)) {
+        wordSet.add(str);
+        checkUniqueSubstring(j);
+        wordSet.delete(str);
+      }
+    }
+  }
+
+  checkUniqueSubstring(0);
+
+  return res;
+};
diff --git a/SeungyeonJi/week9/2023-11-12-WordSearch.js b/SeungyeonJi/week9/2023-11-12-WordSearch.js
new file mode 100644
index 00000000..833163a7
--- /dev/null
+++ b/SeungyeonJi/week9/2023-11-12-WordSearch.js
@@ -0,0 +1,36 @@
+const isOutOfBound = (board, row, col) =>
+  row < 0 || row >= board.length || col < 0 || col >= board[0].length;
+
+const checkNeighbors = (board, word, row, col) => {
+  // Check exit conditions
+  if (!word.length) return true;
+  if (isOutOfBound(board, row, col) || board[row][col] !== word[0])
+    return false;
+
+  // Save some stuff
+  const curChar = board[row][col];
+  const newWord = word.substr(1);
+
+  board[row][col] = 0; // Disable the current character
+
+  // Check if neighbors are fruitful
+  const results =
+    checkNeighbors(board, newWord, row + 1, col) ||
+    checkNeighbors(board, newWord, row - 1, col) ||
+    checkNeighbors(board, newWord, row, col + 1) ||
+    checkNeighbors(board, newWord, row, col - 1);
+
+  // Enable current character
+  board[row][col] = curChar;
+
+  return results;
+};
+
+var exist = function (board, word) {
+  for (let row = 0; row < board.length; row++) {
+    for (let col = 0; col < board[0].length; col++) {
+      if (checkNeighbors(board, word, row, col)) return true;
+    }
+  }
+  return false;
+};